So sorry to hear about that.
I think I can share my experience with you, since my case was refused on June 22, and I also had a LMIA, and it has been re-open now.
My reason for refusal is that I failed at Eligibility verification stage, since I did not provide enough document to support the point that I claimed under CEC.
In my case, I only provide the Letter of Offer twice but did not upload the Letter of Employment which should combine with my incoming proof for the duration I worked, such as T4, Pay Stub and Notice of Assessment.
But I have them in my hand before the AOR. I just did not upload them to make my experience strong, it is my own fault.
After the refusal, I immediately re-enter the pool at the same date June 22 and wait to be selected again.
Then, on June 23 I send the additional document as marked missed on my file to CIC via CSE (IRCC WEBFORM) to please asked the reconsideration to re-open my case, and since I knew where was my case at that time which is CPC Ottawa, so I send them an email with the same document as CSE. Different from CSE, I wrote them a very long explanation about why I think they should re-open my case. And 6 days later, which on June 29, the officer who refuse my application decide to re-open my case.
So my suggestion for you is:
1. Re-enter the pool for sure
2. Send a CSE with your missed PCC to request re-open, as well, with CSE ,als write a explanation letter about why you did not upload the PCC, and why you think they should re-open your case.
3. Try to find out where was your case, and contact with them with same PCC and LOE.
But this is not guaranteed that the officer will accept your PCC and decide to re-open it for you. Since the re-open process could be really long, someone even take about 1 year when I search after my refusal. As I told, it take at least 4-6 weeks. So do not put all your hope to wait for re-open. Just apply it again.
My case may different, since all my R10, ME, Criminality have passed, and I only miss the income proof, and my experience can also be proved by my LMIA application, and since I am CEC, so they also can verify it based on my SIN.
I hope my experience will be helpful, and all the best for you